Attorney General Bill Barr testified before the U.S. Senate in 2019 that he disapproved of the president dangling pardons to ret. Lt. Gen. Michael Flynn in exchange for his silence.
As legal expert Marcy Wheeler pointed out, Sen. Patrick Leahy (D-VT) asked Barr in his confirmation hearing, "Do you believe a president could lawfully issue a pardon in exchange for the recipient's promise not to incriminate him?"
Barr responded, "No, that would be a crime."
The question applies because it was revealed that Flynn was cooperating with special counsel Robert Mueller after pleading guilty. Suddenly, Flynn stopped. It's unknown if Mueller was finished with Flynn or Flynn refused to move forward with additional information. Mueller later said the cooperation was "complete" and proceedings for Flynn could move forward.
When Barr answered questions to the Senate, he seemed unaware that Trump had floated a pardon to Paul Manafort, Flynn and Michael Cohen, Wheeler noted in her 2019 report.
Barr similarly told Sen. Amy Klobuchar (D-MN) that dangling pardons would be a crime when it was her turn to hammer him during the hearing.
In a conversation with MSNBC, former Mueller senior counselor Andrew Weissmann explained that it is another version of Trump's obstruction of justice. That would make 11 examples of obstruction of justice when combined with the ten Mueller compiled in his report.